Recent studies evaluating the effect of slow releasing enteric-coated aspirin formulations have reported contradictory findings regarding the bioavailability of the active molecule in the circulating blood and the length of duration of the inhibitory effect on platelet function. In the present study, we have evaluated the effect of a single dose of two commercially available enteric-coated aspirins on platelet arachidonic acid metabolism and function. A single dose of slow releasing aspirin was as effective as fast acting regular aspirin in its effect on cyclooxygenase activity and platelet function in both human and canine platelets. However, in view of its slow releasing property, the onset of inhibition was considerably delayed compared to the action of fast acting aspirin in those subjects who ingested enteric-coated aspirins.
Bibliographical noteFunding Information:
The authors express their thanks to Dr. K.R. Red& and Ms. Co1l een McAdaragh for their technical assistance. Supported by USPHS grants HL-11880, HL-16833, CA-21737, GM-22167, AM-17697 and a grant from the March of Dimes.